Using the electron configurations of the elements, given in...

Name: Problem 133, Chapter 4: Chemistry
Uploaded: 2021-06-16T17:30:44-08:00
Duration: 3 min 41 s
Channel: Jennifer Hudspeth
Description: Using the electron configurations of the elements, given in Appendix B, and Hund's Rule, determine which elements have a pair of electrons in every occupied orbital (no singles). Are they about half of the elements, rather small in number, or rather large in number? To what groups of elements do they belong?

Using the electron configurations of the elements, given in Appendix B, and Hund's Rule, determine which elements have a pair of electrons in every occupied orbital (no singles). Are they about half of the elements, rather small in number, or rather large in number? To what groups of elements do they belong?

Key Concepts

Electron Configuration

This concept refers to the specific arrangement of electrons in atomic orbitals. It describes how electrons fill orbitals in order of increasing energy, laying the foundation for understanding chemical behavior and periodic trends. Knowing an element’s configuration helps in predicting whether the electrons in any occupied orbital are paired or unpaired.

Hund's Rule

Hund's Rule states that electrons in a set of degenerate orbitals will occupy separate orbitals with parallel spins as much as possible before pairing begins. This minimizes repulsion between electrons and explains why partially filled subshells often have unpaired electrons. If electrons are found to be paired in every orbital, it implies that the subshell is completely filled rather than being midway through its filling.

Closed?Shell Configurations

A closed-shell configuration occurs when all orbitals in a subshell are fully occupied by pairs of electrons. In such cases, no orbital contains a single (unpaired) electron. Elements with closed shells typically have particularly stable electron configurations, which can be seen in groups like the noble gases or in elements with completely filled s, p, d, or f subshells.

Periodic Table Groupings

The periodic table is organized into groups based on recurring patterns in electron configuration. Elements that have every occupied orbital containing a pair of electrons usually belong to groups with closed subshells. This includes the noble gases in the p?block, alkaline earth metals with a completely filled outer s subshell, and certain transition or lanthanide/actinide elements that exhibit filled d or f subshells. These groups are relatively few compared to all elements, indicating that such fully paired configurations are small in number overall.

Transcript

00:02 Hi there.

00:03 Let's look at question number 133.

00:07 In question number 133, they would like for us to use appendix table b and state all of the elements that have full orbitals.

00:18 In other words, they have zero unpaired electrons.

00:23 So we can use that table to do that, or we could use the periodic table.

00:27 I'm going to use the periodic table because i know in the s block elements, for example, group 2 ends with a full s -orbital, or a full s2, in other words.

00:42 So all of those elements are going to have all of their orbitals full.

00:47 So first of all, that includes helium.

00:51 Remember helium, even though it's in period 1, is full with 1s2.

00:57 And then each of the group 2 elements belong here.

01:00 Burium, magnesium, calcium, calcium, strontium, barium, and radium.

01:15 So those all have full orbitals.

01:18 Next i want to look at the d block elements.

01:20 And specifically, i want to look at the last group of d block elements because they are going to have their d10 filled.

01:29 So that will include zinc, cadmium, and mercury.

01:39 Following that, let's look at the p group elements.

01:42 The ones that end with p6 will have all of their orbitals...